Biogenic vs. abiogenic magnetite nanoparticles: A XMCD study

Claire Carvallo (1) , Philippe Sainctavit (1) , Marie-Anne Arrio (1) , N. Menguy (1) , Yuheng Wang (1) , Georges Ona-Nguema (1) , Sandrine Brice-Profeta (1, 2)

1 IMPMC - Institut de minéralogie et de physique des milieux condensés
2 ENSEEG/LTPCM

X-ray magnetic circular dichroism (XMCD) experiments were carried out to compare the Fe2+/ Fe3+ ratio in nanomagnetite chemically produced from lepidocrocite and nanomagnetite biogenically produced by the Fe-reducing bacterium Shewanella putrefaciens. Together with TEM imaging, these measurements showed that the biotic magnetite nanoparticles were of excellent quality, with small size dispersion and high crystallinity. From the XMCD measurements, it could be shown that the biogenic nanomagnetite contained a higher amount of Fe2+ than the abiogenic nanomagnetite.

Mots clés: Nanomagnetite; XMCD; Shewanella putrefaciens; biomineralization

Domaines: Minéralogie; Physique Quantique [quant-ph]

Claire Carvallo, Philippe Sainctavit, Marie-Anne Arrio, N. Menguy, Yuheng Wang, et al.. Biogenic vs. abiogenic magnetite nanoparticles: A XMCD study. The American Mineralogist, 2008, 93, pp.880-885. ⟨10.2138/am.2008.2713⟩. ⟨hal-00325482⟩